AS WC says
Aztec book states 'important to move prop control in and out of feather position very quickly to prevent dropping more than 500 rpm, and causing excessive manifold pressure'.
The normal start point for this check is 1500 rpm, or so I was taught, so min revs are 1000rpm.
I believed the speed of the in and out was to avoid ending up with a feathered prop during pre flight checks, is this so?